Sheriff John Peper was killed in an automobile accident on U.S. 52 near Lebanon as he and a deputy responded to the scene of another accident. Their vehicle went out of control on the sleet-covered roadway and flipped over. Sheriff Peper suffered fatal injuries when he was thrown into the back seat.

Sheriff Peper had served with the Boone County Sheriff's Department for only five weeks. He was survived by his wife who was appointed as sheriff to serve the remainder of her husband's term. She was the first female sheriff of Boone County and the third female to serve as a sheriff in the state of Indiana. In 2010, U.S. 52, four miles north of Lebanon in Boone County, was dedicated the Sheriff John H. Peper Highway in his honor.